


Drunk On You

by Castrealm



Category: IDOLiSH7 (Video Game)
Genre: Alpha Kujou Tenn, Alpha/Beta/Omega Dynamics, Beta Ousaka Sougo, Dirty Talk, Dubious Consent, Implied/Referenced Underage Drinking, Implied/Referenced Underage Sex, Intersex Nanase Riku, M/M, Mating Cycles/In Heat, Omega Nanase Riku, Past TennRiku, Plot What Plot/Porn Without Plot, Vaginal Sex, kind of, mentions of mpreg
Language: English
Status: Completed
Published: 2020-11-24
Updated: 2020-11-24
Packaged: 2021-03-09 18:15:25
Rating: Explicit
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 2,193
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/27700565
Author URL: https://archiveofourown.org/users/Castrealm/pseuds/Castrealm
Summary: Sougo gets drunk on a little alcohol, and a lot of Riku.
Relationships: Kujou Tenn/Nanase Riku - Implied, Nanase Riku/Ousaka Sougo
Kudos: 29





	Drunk On You

**Author's Note:**

> I was thirsty, so I got me a nice, tall glass of SouRiku, with a side of TennRiku. 
> 
> For those of you who are new to my works and unfamiliar with my idea of omegaverse, gather around for a little biology lesson :)
> 
> Your primary gender (male & female) is determined based on your X and Y chromosomes (X and X is female, X and Y is male, pretty basic stuff), meanwhile your secondary gender (omega, beta, alpha) determines your sexual organs and reproductive system.
> 
> So, all omega’s (regardless of primary gender) and female betas have a vagina, a uterus and ovaries. Meanwhile, all alpha’s and male beta’s have a penis, testicles and sperm. But, of course all alpha’s penises come equipped with a little extra component, which is a bulbous glandus (or a knot). On the other hand, the only difference between a male omega and female omega is that the male omega’s clitoris is slightly larger.
> 
> So, yes, despite identifying as male, Riku does have a vagina in this! Hence, the intersex tag. 
> 
> The reason omega’s go into heat and female betas do not, despite having the same reproductive system is because humanity evolved from animals, and during this time their population was very limited so heat cycles and pheromones were a way to encourage reproduction. Omega’s and alpha’s simply retained their anatomy and instinctive coding from their ancestors. On the other hand, beta’s are basically an evolutionized version of alpha’s and omega’s because mankind’s numbers are stable and they no longer need to promote breeding.
> 
> Well, without further ado, let’s start the sinning!

_This was a mistake_. 

The thought had surfaced in Sougo’s mind the moment a pair of arms snaked around his neck, pulling him until his face was a hair’s breadth away from that of a certain red-headed center. 

“Tenn- _nii_ ,” not expecting to hear Riku say the name of his older twin brother, Sougo instinctively stiffened, “don’t leave me alone again. Stay with me. Why don’t we play, like we used to?” Riku purred suggestively, his warm breath ghosting across Sougo’s already flushed cheeks. 

From this proximity, it was only natural that Sougo could smell the alcohol and chocolate on the redhead's breath as he spoke. However, the strong scent of liquor couldn’t compare to the volumes of omega pheromones circulating throughout Riku’s bedroom. And it was in that moment, as the skin of his lips hovered dangerously close to Riku’s own, that he started to reflect on how the situation had turned out like this. 

Yamato was currently in the process of filming for a popular drama, and had returned to the dorms that afternoon sporting a box of chocolates that he had received from one of his co-stars, who also happened to be a fan of his. However, upon closer inspection, the box of chocolates he had received wasn’t some ordinary box of chocolates; they were liquor chocolates. 

That evening, fellow idol groups had been invited to the Idolish7 dorms to celebrate. Naturally, this included Trigger, as well as Riku’s older twin brother, Tenn Kujo, whom the omega was naturally excited to see. 

Since the moment he arrived, Riku had tried desperately to hold a conversation with his brother, but Trigger’s frigid center was more interested in striking up conversation with others aside from Riku. When the redhead wasn’t following him around the room like a lost puppy, he was awkwardly shuffling about where Tenn had left him in favor of approaching someone else. 

Naturally, Tenn’s lack of excitement to see his younger twin brother in return depressed Riku, forcing him to retreat to the kitchen, where he found Yamato’s chocolates. 

Wanting to console himself, Riku took the liberty of eating one, unbeknownst to him that the chocolates were alcoholic. And although the volume of alcohol in each candy wasn’t much, it’s a little known fact that Riku is an extreme lightweight when it comes to alcohol.

Needless to say, after doing so, Riku was totally inebriated. 

On the other hand, Sougo had been so nervous to find himself basking in the presence of such renowned idol groups that he ended up drinking too. However, before he could completely drown his nerves, that was when Riku had come stumbling out of the kitchen in his drunken state. 

Sougo was taken off guard when the redhead suddenly attached himself to his arm, meanwhile whining something incomprehensible to the beta. 

Afterwards, Sougo made the conscious decision to escort the omega to his bedroom to sleep for the night. 

The beta had managed to tuck Riku into bed, and was about to take his leave when the omega yanked him down without issuing any warning whatsoever. 

Now, here they were. However, since this whole ordeal started, Riku had somehow managed to flip their positions so Sougo was now laying with his back pressed to the mattress, giving Riku room to straddle his waist. 

The tipsy part of Sougo’s hazy mind, which also happened to be under the influence of omega pheromones, couldn’t resist conjuring up the illusion that Riku didn’t look like his usual, innocent self. 

The redhead was currently looking down the bridge of his nose at the beta, a lopsided but lascivious grin plastered on his face. Those previously bright vermillion eyes were now glazed over with what Sougo could only identify as drunken lust. 

_He looks… deliciously slutty_. Whether it was an effect of the sweet pheromones permeating the air or not was anyone’s guess, but in that moment, Sougo felt his cock throb. 

“Don’t you remember that night, Tenn- _nii_? How your big cock felt in my tight omega pussy. You told me you loved it. Hey, let’s do that again. Fuck me like you did back then, Tenn- _nii_.” Riku gasped, grinding his ass back against Sougo’s steadily growing erection. 

As expected, the friction elicited a mantra of groans from the beta. 

“Riku- _kun_ … _mm_ … no. We can’t.” Sougo panted. Yet, regardless of how much he protested against this, his rationality was losing drastically to his growing desires. Despite being in a buzzed state before, Sougo felt like Riku’s pheromones were enough to intoxicate him completely. 

“You’re lying. I know you want to, Tenn- _nii_. You want to, because I want you to. I want you to fuck me deep. I want to feel you all the way up inside my baby room.” Sweeping his tongue over his top lip, Riku put on a lewd display as he ran his fingertips across the front of his stomach, just below his navel, as if to show Sougo where his womb was located. The beta couldn’t resist the sharp inhale he took at the sight. 

Nevertheless, Sougo mostly couldn’t handle how Riku was moaning like an actress in a porno as he rocked back and forth on the beta’s clothed dick.

 _An omega’s pheromones are enough to drive an alpha to murder, and a beta to madness_. Sougo would never doubt that phrase for as long as he lived. 

“Riku- _kun_ … no, you’re wrong. I-I’m not Kujo Tenn.” As he spoke, Sougo’s tongue felt as though it was caked with mud. It felt heavy in his mouth, making it difficult to speak. Regardless of his words, a part of Sougo prayed to whatever deity was out there that Riku wouldn’t come to his senses. For the love of everything that was holy, he didn’t want this to stop. 

As if having heard his prayers, Riku simply chuckled at his words. The omega reached underneath him so as to stroke at the hard mass in the front of Sougo’s pants, earning a hiss of pleasure. However, Sougo desperately wanted Riku to touch it directly, instead of through the material of his clothes. “There’s no way I would mistake this big cock for anyone else. Only my Tenn- _nii_ has a dick this impressive.” 

“Oh my god…” Sougo huffed, draping an arm across his eyes. He was in disbelief that the pure and innocent Riku he knew could be this sexy and desirable. It felt as though his sanity was slipping. “Riku- _kun_ , please…” He whispered, sinking his teeth into the skin of his lips as his hips instinctively bucked against Riku’s hand, which was still rubbing circles in his bulge. 

“That looks painful, Tenn- _nii_.” Riku moaned, biting into his lip upon feeling Sougo’s cock throb through the fabric. “I bet you just wanna hurry up and shove it inside me already. Don’t worry about holding back, my pussy remembers your shape. So you can shove it in and stir up my omega cunt as much as you like.” The omega whispered seductively, and it was in that moment that Sougo felt something inside his head snap.

He must’ve succumbed to his instincts, because the next thing the beta knew he was on top of Riku, settled between the redheads open thighs. However, rather than look the least bit surprised by the rough treatment, Riku looked even more lewd than before, as if being pinned underneath Sougo was where he belonged. 

As if his body was moving on autopilot, Sougo tore Riku’s pants and underwear from his bare legs, and continued to unfasten the front of his own pants, fishing out his painfully stiff erection with relative ease. 

He gave it a few pumps, coating it in his own precum, before lining up the swollen crown of his cock with Riku’s omega pussy, which was completely soaked. It gave the beta the impression that the redhead had already came several times from the time he took Sougo hostage. 

The beta’s head was swimming. 

He hesitated as he considered getting a condom, however he perished the thought when, without warning, Riku folded his legs behind Sougo’s lower back. Using every muscle in his legs, he pulled the beta forward, sending him plunging deep inside in one swift motion. 

Sougo echoed Riku as the couple moaned in ecstasy at the delicious sensation. It was enough to send Sougo into a state of delirium. 

Much like his personality, Riku’s insides were so warm and welcoming. 

The fleshy walls caressed, squeezed and coiled around Sougo’s member as if welcoming him back from a prolonged absence. It was tight and wet, and made Sougo’s head feel numb and spacey. Instincts told him to piston his hips. 

Fortunately however, he at least had enough self-control to keep from fucking into Riku with abandon before the omega gave him permission to do so. 

“Tenn- _nii_! Ah, Tenn- _nii_! You’re really inside me! Your cock is so hot! It feels so good!” Riku was moaning like a bitch in heat. “Tenn- _nii_! Hurry up and move! Fuck me as deep as you can!” The omega took the liberty of pushing his heels into Sougo’s spine, as if silently encouraging him to hurry up and swing his hips - and, well, who was Sougo to deny his precious center. 

“Fuck me harder!” Riku practically cried, looping his arms around Sougo’s neck so as to claw at his shoulder blades through the material of his shirt. Nevertheless, it only served to spur Sougo on. Drunk on omega pheromones, the beta quickly fell into a bruising pace that elicited lewd, wet, slapping noises with every push of his hips. 

“Riku- _kun_ … Riku- _kun_ , Riku- _kun_ …” He panted the omega’s name under his breath as though it were a lifeline; like a fan at a concert. Meanwhile, the omega only cried the name of his older twin brother. However, Sougo was too invested in the pleasure he felt in his cock that he couldn’t bring himself to really mind. “Feels so good… You feel so good inside. It’s driving me crazy.” 

“Tenn- _nii_! _Ah_! T-Tenn- _nii_ …! I love… _mm_ , Tenn- _nii_ the most! I love you! _Ah_ …! I love you! I always have! Tenn- _nii_! Please… kiss me!” 

Without having to ask twice, Sougo sprung forward, slotting their mouths together in a wet and sloppy kiss. 

“Riku- _kun_ …! I-I’m close…!” Sougo huffed, the movement of his hips was gradually starting to lose rhythm, becoming more erratic as the heat in his gut burned hotter. It was like a loaded spring, waiting to be uncoiled. 

“Do it inside me, Tenn- _nii_! Please! I want you to cum inside, just like you did back then. Knock me up! I want to give birth to your babies, Tenn- _nii_!” Riku continued to ramble on, however Sougo found himself too focused on chasing his orgasm. It wasn’t until Riku cried, “Give me your knot!” that Sougo briefly returned to his senses. He needed to make this illusion real, if he was going to be able to convince a sober Riku that it was all a fever dream. 

Afterall, he didn’t want to psychologically traumatize the omega for having sex with his fellow idol, while thinking it was his older twin brother. 

Courtesy of his quick thinking, Sougo did his best to replicate an alpha’s knot by pushing and curling his fingers inside of Riku, slotting them alongside his pulsing shaft. He pushed his fingertips as hard as he could against the walls of Riku’s birth canal and prayed for the best. However, his strength faltered as his vision was suddenly overcome with television static. 

With one final snap of his hips, Sougo pushed inside until the head of his dick was crammed against Riku’s soft cervix. His mind went completely blank, and the only two things he found himself able to focus on was the pleasant prickling sensation in his fingertips, and the satisfying feeling of white-heat erupting from his cock. 

Upon coming down from his euphoria, the first thing Sougo bothered to notice was that the sweet omega pheromones were completely absent. Secondly, after reaching his climax, Riku had lost consciousness. 

Needless to say, the sight of the red headed omega out cold, Sougo’s ejaculate slowly oozing out from between deliciously pale thighs, was enough to slap some sense into the beta, filling his previously jelly-like bones with both fear and sheer panic.

Sougo didn’t know what was more fucked up: the fact that he had practically raped his center, or the fact that Riku thought he was Kujo Tenn while being raped. 

After cleaning the sleeping omega up and tucking him in like he was originally intending, Sougo decided that now more than ever he would need to drink until he couldn’t remember what just happened. 

_I had sex with Kujo Tenn’s younger twin brother…_

_… and I liked it._

_I had sex with Kujo Tenn’s younger twin brother…_

_… and it was hot._

That was his last thought upon losing consciousness, and that was his first thought upon waking up the next morning. 

Fortunately for Sougo and Riku though, it was all just a weird, alcohol-induced dream…

… Right?

**Author's Note:**

>  **Riku** : Sougo- _san_ looks just like Tenn- _nii_!  
>  **My Horny Brain at 3 AM** :
> 
>  _Siiiiigghhhhhh_. If there’s one thing I love in this world, it’s a slutty Riku. Well, I hope you enjoyed! 
> 
> Let me know what you think with a comment, or feed me a delicious kudos *0*


End file.
